Now let's get this straight. Japanese is a complicated language and this kanji [姦] means many, many things in both Chinese and Japanese. Honestly it depends on the context. I also found out that [姦] can mean noisy in a kind of boisterous way. There are different kinds of noisy, there are different kinds of wicked, there are different degrees of rape. They all have terms in English as well as in Japanese and Chinese. It's just that sometimes they are written the same way and pronounced differently, or sometimes there may be more kana at the end of the kanji to change its meaning.

I can't speak for the Japanese, but considering kanji are derived from Chinese hanzi, maybe I can help out?

In Chinese, this character does exist, but the meaning is more sinister. It comes out as "wicked", "treacherous" (adj) or "traitor" (noun). See www.nciku.com/search/zh/detail....

I'm not sure if it would have the same meaning, but usually Chinese hanzi are the same as kanji. If so, this points to a sexist ideology. It's important to remember that the characters are 2500ish years old, so views have changed, but even so, I can't say I like it.